Atmail is a fully-featured email server and Webmail client, allowing users to send and receive email via a Web browser or mobile device. It has full support for
IMAP mailboxes, and an optional email-server mode that uses EXIM as the MTA. Features include a scheduler, MySQL backend support, spell-check, address book, calendar user preferences, multiple accounts, SpamAssassin support, migration scripts from other mail servers, a customizable interface, an attractive AJAX interface, an optional group sharing Calendar/Addressbook, and an Outlook plugin to sync Contacts/Tasks/Calendar data between a Desktop, Mobile, and Webmail client or other email users.

AbiWord is a free word processing program similar to Microsoft Word. It is suitable for a wide variety of word processing tasks. It allows you to collaborate with multiple people on one document at the same time. It is tightly integrated with the AbiCollab.net Web service, which lets you store documents online, allows easy document sharing with your friends, and performs format conversions on the fly.

CGIProxy is a Perl CGI script that acts as an Internet proxy. Through it, you can retrieve resources that may be inaccessible from your own machine. The user is kept as anonymous as possible from any servers. HTTP and FTP are supported, and optionally SSL. Common uses include censorship circumvention, VPN-like setups, anonymous proxies, personal proxies, and others. Options include text-only browsing (to save bandwidth), selective cookie and script removal, simple ad filtering, access restriction by server, encoded target URLs and cookies, configuration by end user, and much more (currently over 70 config options). Javascript and Flash are fully supported. Messages are in 14 languages so far. Can be installed as a CGI script, a mod_perl script, a FastCGI script, or with its own embedded secure HTTP server. An online demo is available.

GCompris is an educational software suite with numerous activities for children aged 2 to 10. Some of the activities are game-orientated, but nonetheless still educational. These include computer discovery (keyboard, mouse, different mouse gestures), algebra (table memory, enumeration, double entry table, mirror image), science (the canal lock, the water cycle, the submarine, electric simulation), geography (place the country on the map), games (chess, memory, connect 4, oware, sudoku), reading practice, and others (learn to tell time, puzzles of famous paintings, vector drawing, cartoon making, etc.). It currently offers in excess of 100 activities, and more are being developed.

Mantis Bug Tracker (MantisBT) is a Web-based issue tracking system that is both simple to use and highly customisable. A plugin system allows users to easily create and add new features. MantisBT is over 10 years old and is actively developed.

phpMyAdmin is a tool intended to handle the
administration of MySQL over the Web. It can
create, rename, and drop databases,
create/drop/alter tables, delete/edit/add fields,
execute any SQL statement, manage keys on fields,
create dumps of tables and databases,
export/import CSV data, and administrate one
single database and multiple MySQL servers.

KuickShow displays images using all available space, without wasting it with bars or menus. It also has smart automatic zooming which scales images according to size. You can use the integrated file browser to choose images, or navigate through a folder with the mousewheel or the keyboard. It also has fullscreen view and slideshow, and supports a wide range of image formats.

Newscoop (formerly known as Campsite) is an open content management system for professional journalists. Features for the modern newsroom include multiple author management, issue-and-section based publishing, geolocation, and multilingual content management. The enterprise-standard journalist’s dashboard and a templating engine supporting anything from HTML5 to mobile complete this fast production and publishing system.

The Apache Open For Business Project is an enterprise automation software project that includes ERP, CRM, E-Business/E-Commerce, SCM, MRP, and CMMS/EAM functions. It is a foundation and starting point for enterprise solutions and can certainly be used out of the box, but is also great for creating specialized applications.